Conducting and reinforcing carbon black networks in semiconductive materials

Conductive filler particles mixed into a polymer matrix form a network that can carry an electrical current as well as a mechanical load. This work discusses the correlation between the electrical network and reinforcing network. It is concluded that both networks are not identical, although this is suggested by the percolation theory. An analysis of the frequency dependence of the conductivity suggests that variations in the conductivity are not necessarily due to an increased number of contact points between filler particles that would lead to stronger reinforcement. Instead, there is indication that variations in the conductivity are substantially affected by changes in the gap width between filler particles.